PROJECT SUMMARY Chronic pain has emerged as an urgent age-related health issue that significantly compromises physical functioning and quality of life, with the adverse effects amplified by both obesity and sedentary behavior. The annual cost of pain in the United States is nearly 30% higher than the combined costs of cancer and diabetes. In 2016, the NIH called for a National Pain Strategy to: 1) expand non-pharmacological treatment options in older adults, who are particularly susceptible to the side effects of opioid and other pain medications; 2) develop accessible treatments that are tailored to individuals; and 3) increase the development of self-management programs for chronic pain. The purpose of this R-21 is to develop and test the feasibility and acceptability of a novel, patient-centered intervention to reduce chronic pain and improve physical functioning in older adults, leveraging the combination of telecoaching and individually-adaptive mHealth tools to decrease both body mass and sedentary behavior. The proposal consists of two phases. The first phase will use an iterative user-centered design process to develop the mHealth application, to adapt the weight loss and sedentary behavior components of the intervention to a telecoaching model, and to evaluate the usability and feasibility of the intervention for obese, older adults with chronic pain. In the second phase we will conduct a pilot randomized controlled trial to provide initial evidence for effect sizes (pain and physical function) associated with the proposed intervention, and to estimate the sample size needed for a full scale randomized controlled trial design that compare the effects of the intervention versus usual care on pain ratings and physical function in overweight/obese older adults with chronic pain.